神仙题.为啥我第一眼看上去以为是个普及题 路径有两种,第一种是从 LCA 一边下去的,第二种是从 LCA 两边都下去了的. 先考虑第一种. 先枚举路径长度 \(h\). 当 LCA 编号是 \(x\) 时,且所有儿子都是往左走时,和为 \((2^h-1)x\):所有儿子都往右走时,和为 \((2^h-1)x+2^h-1\).显然 \((2^h-1)x\le s\le (2^h-1)x+2^h-1\). 考虑从下往上第 \(i\) 个点从左儿子变成右儿子时(其它不变),总和会增加 \(2^i-1\…

目录 简单的 组合的 题目链接 简单的 设从节点\(x\)开始不断往左儿子走h-1步,则编号和为\(x\sum_{i=0}^{h-1}2^i=x(2^h-1)\). 若倒数第\(i\)步走向的是右儿子,则编号和会增加\(\sum_{j=0}^{i-1}2^j=2^i-1\). 这样,从\(x\)往下走形成的长为\(h\)的链中,其中倒数\(i,i\in T\)步时走向右儿子,倒数\(i,i\not\in T\)步走向左儿子,这样得到的编号和为 \[ x(2^h-1)+\sum_{i\in T}2…

Given a binary tree, return all root-to-leaf paths.Example Given the following binary tree: 1 /   \2     3 \  5 All root-to-leaf paths are: [  "1->2->5",  "1->3"] LeetCode上的原题,请参见我之前的博客Binary Tree Paths. 解法一: class Solution {…

Binary Tree Paths Given a binary tree, return all root-to-leaf paths. Given the following binary tree: 1 / \ 2 3 \ 5 All root-to-leaf paths are: [ "1->2->5", "1->3" ] As mentioned in the problem we want to get all root-to-leaf…

Binary Tree Paths Given a binary tree, return all root-to-leaf paths. For example, given the following binary tree: 1 / \ 2 3 \ 5 All root-to-leaf paths are: ["1->2->5", "1->3"] Credits:Special thanks to @jianchao.li.fighter f…

257. Binary Tree Paths Total Accepted: 29282 Total Submissions: 113527 Difficulty: Easy Given a binary tree, return all root-to-leaf paths. For example, given the following binary tree: 1 / \ 2 3 \ 5 All root-to-leaf paths are: ["1->2->5",…

257. Binary Tree Paths Easy Given a binary tree, return all root-to-leaf paths. Note: A leaf is a node with no children. Example: Input: 1 / \ 2 3 \ 5 Output: ["1->2->5", "1->3"] Explanation: All root-to-leaf paths are: 1->…

Given a binary tree, return all root-to-leaf paths. For example, given the following binary tree: 1 / \ 2 3 \ 5 All root-to-leaf paths are: ["1->2->5", "1->3"] 这道题给我们一个二叉树,让我们返回所有根到叶节点的路径,跟之前那道Path Sum II 二叉树路径之和之二很类似,比那道稍微简单一…

Given a binary tree, return all root-to-leaf paths. For example, given the following binary tree: 1 / \ 2 3 \ 5 All root-to-leaf paths are: ["1->2->5", "1->3"] 思路:用两个stack<TreeNode*> in , s; in : 记录当前的路径 p  , 和vector<…

Given a binary tree, return all root-to-leaf paths. For example, given the following binary tree: 1 / \ 2 3 \ 5 All root-to-leaf paths are: ["1->2->5", "1->3"] 本题可以用DFS或者BFS. 解法一: DFS,参考自九章算法 class Solution: # @param {TreeNode…

Description: Given a binary tree, return all root-to-leaf paths. For example, given the following binary tree: 1 / \ 2 3 \ 5 All root-to-leaf paths are: ["1->2->5", "1->3"] Code: void allPath(TreeNode*root, vector<string>…

Given a binary tree, return all root-to-leaf paths. For example, given the following binary tree: 1 / \ 2 3 \ 5 All root-to-leaf paths are: ["1->2->5", "1->3"] 思想:递归代码如下: /** * Definition for a binary tree node. * public class…

题目: Given a binary tree, return all root-to-leaf paths. For example, given the following binary tree: 1 / \ 2 3 \ 5 All root-to-leaf paths are: ["1->2->5", "1->3"] 链接: http://leetcode.com/problems/binary-tree-paths/ 题解: 求Binar…

题目描述: Given a binary tree, return all root-to-leaf paths. For example, given the following binary tree: 1 / \ 2 3 \ 5 All root-to-leaf paths are: ["1->2->5", "1->3"] 解题思路: 使用递归法. 代码如下: /** * Definition for a binary tree node.…

Question Given a binary tree, return all root-to-leaf paths. For example, given the following binary tree: 1 / \ 2 3 \ 5 All root-to-leaf paths are: ["1->2->5", "1->3"] Solution -- Recursive We can not apply inorder traversal…

题目: Given a binary tree, return all root-to-leaf paths. For example, given the following binary tree: 1 / \ 2 3 \ 5 All root-to-leaf paths are: ["1->2->5", "1->3"] 求一个二叉树的所有路径 代码: /** * Definition for a binary tree node. * str…

Given a binary tree, return all root-to-leaf paths. For example, given the following binary tree: 1 / \ 2 3 \ 5 All root-to-leaf paths are: ["1->2->5", "1->3"] Credits:Special thanks to @jianchao.li.fighter for adding this pro…

Given a binary tree, return all root-to-leaf paths. For example, given the following binary tree: 1 / \ 2 3 \ 5 All root-to-leaf paths are: ["1->2->5", "1->3"] Credits:Special thanks to @jianchao.li.fighter for adding this pro…

Given a binary tree, return all root-to-leaf paths. For example, given the following binary tree: 1 / \ 2 3 \ 5 All root-to-leaf paths are: ["1->2->5", "1->3"] 题目标签:Tree 这道题目给了我们一个二叉树,让我们记录所有的路径,返回一个array string list. 我们可以另外设一…

一天一道LeetCode 本系列文章已全部上传至我的github,地址:ZeeCoder's Github 欢迎大家关注我的新浪微博,我的新浪微博 欢迎转载,转载请注明出处 (一)题目 Given a binary tree, return all root-to-leaf paths. For example, given the following binary tree: 1 / \ 2 3 \ 5 All root-to-leaf paths are: ["1->2->5&q…

题目: Given a binary tree, return all root-to-leaf paths. For example, given the following binary tree: 1 / \ 2 3 \ 5 All root-to-leaf paths are: ["1->2->5", "1->3"] 思路: 题意:求二叉树根到叶子的所有路径 二叉树的问题,没有一次递归解决不了的,如果有,那就两次,判断左右子树,都为空是叶子…

Given a binary tree, return all root-to-leaf paths. Note: A leaf is a node with no children. Example: Input: 1 / \ 2 3 \ 5 Output: ["1->2->5", "1->3"] Explanation: All root-to-leaf paths are: 1->2->5, 1->3 给定一个二叉树,返回所…

Given a binary tree, return all root-to-leaf paths. Note: A leaf is a node with no children. Example: Input: 1 / \ 2 3 \ 5 Output: ["1->2->5", "1->3"] Explanation: All root-to-leaf paths are: 1->2->5, 1->3 Iteration:…

Given a binary tree, return all root-to-leaf paths. Note: A leaf is a node with no children. Example: Input: 1 / \ 2 3 \ 5 Output: ["1->2->5", "1->3"] Explanation: All root-to-leaf paths are: 1->2->5, 1->3 题目 给定一棵二叉树,…

Description: Given a binary tree, return all root-to-leaf paths. For example, given the following binary tree: 1 / \ 2 3 \ 5 All root-to-leaf paths are: ["1->2->5", "1->3"] /** * Definition for a binary tree node. * public cla…

［抄题］: Given a binary tree, return all root-to-leaf paths. For example, given the following binary tree: 1 / \ 2 3 \ 5 All root-to-leaf paths are: ["1->2->5", "1->3"] [暴力解法]: 时间分析: 空间分析: ［奇葩corner case］: ［奇葩输出］: 看到["1->…

Given a binary tree, return all root-to-leaf paths. For example, given the following binary tree: 1 / \ 2 3 \ 5 All root-to-leaf paths are: ["1->2->5", "1->3"] 简单的遍历查找路径问题,代码如下: /** * Definition for a binary tree node. * struc…

Given a binary tree, return all root-to-leaf paths. Note: A leaf is a node with no children. Example: Input: 1 / \ 2 3 \ 5 Output: ["1->2->5", "1->3"] Explanation: All root-to-leaf paths are: 1->2->5, 1->3 Idea: trave…

Given a binary tree, return all root-to-leaf paths. Note: A leaf is a node with no children. Example: Input: 1 / \ 2 3 \ 5 Output: ["1->2->5", "1->3"] Explanation: All root-to-leaf paths are: 1->2->5, 1->3 /** * Defin…

Given a binary tree, return all root-to-leaf paths. For example, given the following binary tree: 1 / \ 2 3 \ 5 All root-to-leaf paths are: ["1->2->5", "1->3"] 给一个二叉树,返回所有根到叶节点的路径. Java: /** * Definition for a binary tree node…